Investigating the Effects of Probiotic Yogurt on Reducing the Levels of Environmental Toxins Among School Children in Mwanza, Tanzania

Not Applicable

Completed

• Conditions: C535854; D004786
• Interventions: Dietary Supplement: Lactobacillus rhamnosus GR-1; Dietary Supplement: Pasteurized Whole Milk

• Registration Number: NCT01904513
• Lead Sponsor: Western University, Canada

Brief Summary

The primary objective of this pilot study is to determine if consumption of a probiotic yogurt causes reduced levels of environmental toxins in a group of school-aged Tanzanian children. The secondary objective is to determine the levels of environmental toxins in Tanzanian children and compare these to literature values of levels believed to negatively affect health and development. The third objective is to analyze the intestinal microbiota of the children and to determine if consumption of a probiotic yogurt has a significant affect on the microbiota composition.

Detailed Description

A group of 60 first year students from the Lake Primary School will be recruited for inclusion into the study. After gaining consent from the child's caregiver, each child will be given a participant number and blood, urine and fecal samples will be collected from each child by qualified personnel from NIMR. Children will be randomized into two groups (n=30) to match age, sex and weight, one of which will receive a 100 g probiotic yogurt containing Lactobacillus rhamnosus GR-1 while the other group will receive an equivalent portion of milk. After 30 days of consuming the yogurt or milk, samples will again be collected.

Samples will be shipped back to London, Ontario Canada on dry ice for analysis. Blood and urine will be analyzed via high-resolution sector field inductively coupled plasma mass spectrometry (HR-SF-ICP-MS) to determine levels of toxic heavy metals (Mercury, Lead, Cadmium, Arsenic). This will be carried out by the London Health Sciences Trace Elements laboratory in Canada. Urine will also be analyzed via gas chromatography/ mass spectrometry (GC-MS) to determine levels of pesticides at the Biotron Facility (University of Western Ontario). We will also examine urine via NMR for potential host metabolic changes in response to probiotic instillation.

Bacterial community DNA samples will be extracted and analyzed to determine the gastrointestinal microbiota of the children both before and after administration of the probiotic yogurt to determine the effect of the yogurt on the gut microbiome. Briefly, DNA will be extracted with the Qiagen Stool DNA extraction kit and bacterial community 16S rRNA genes will amplified using barcoded primers specific for a variable region within the gene. The samples will be pooled and sequenced on the Ion Torrent platform (London Regional Genomics Center, Canada). Reads are then processed and analyzed using custom scripts as well as the Quantitative Insights Into Microbial Ecology (QIIME) tool, which is the leading package for microbiota analysis.

Study Timeline

• Study Start: 2012-12
• Primary Completion: 2012-12
• Study First Submitted: 2013-07-04
• Study First Submitted QC: 2013-07-17
• Study First Posted: 2013-07-22
• Study Completion: 2013-08
• Status Verified: 2013-12
• Last Update Submitted: 2013-12-16
• Last Update Posted: 2013-12-17

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 44

Inclusion Criteria

• Aged 6-10
• Attends Lake Primary School (Mwanza, Tanzania)

Exclusion Criteria

• Allergic to milk/ milk products
• Lactose intolerant

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Probiotic	Lactobacillus rhamnosus GR-1	Daily consumption of yogurt supplemented with L. rhamnosus GR-1 at \~10\^10 CFU/day
Milk	Pasteurized Whole Milk	Daily consumption of pasteurized whole milk

Primary Outcome Measures

Name	Time	Method
Changes in Body Toxin Levels	Before and after the 25 day intervention period.	Body toxin levels (metals, pesticides) by HR-SF-ICP-MS and GC/MS.

Secondary Outcome Measures

Name	Time	Method
Changes in host metabolism due to probiotic instillation	Before and after the 25 day intervention period.	Host metabolic shifts as measured by NMR from urine
Changes in Microbiota Composition	Before and after the 25 day intervention period.	Stool microbiota composition shifts as determined by 16S rRNA profiling.
Microbes linked to host toxin levels	Initial sample collection visit	Microbes, as determined via 16S rRNA sequencing, associated with high toxin levels.

Trial Locations

Locations (1)

National Institute for Medical Research; 🇹🇿 Mwanza, Tanzania